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"Sridhar" <sridhar_at_inapp.com> wrote:
>But when i try to connect using a program, to the server or from any other
>client machines, the ORA12537 error is coming. ORA-12537 TNS Connection
>closed.
This happens I think when the FIN bit in the TCP packet is set. With the bit enabled, the protocol stack closes the connection.
This is/should be driven from the application side - i.e. when you type EXIT in SQL*Plus it closes the socket which in turn causes the TCP connection to be shutdown.
The only problem I have ever ran into with this specific Oracle warning message (not an error message mind you!) was back on OPS 7.3.3 on a Unix cluster. This happened intermittantly. We even ran physical network traffic sniffers and could not determine why the FIN bit was set. The problem disappeared after we did an upgrade to the Unix o/s - we put that one down to an undocumented bug of sorts in the kernel that got fixed.
I doubt though that these sorts of low level bugs are still around. Solaris and Oracle are suppose to be mature. ;-)
Attempt to isloate the problem. Does it happen irrespective of the Oracle schema/user used? Does it only happen in SQL*Plus, or also with tools like export and SQL*Loader. Have a look at your listener configuration. Turn on the trace option for both the listener and SQL*Net/NET8 client. Check what the logs say. Make sure that there is nothing "funny" on Solaris running that could interfere with the standard networking - firewalls, proxies.. or a sysadmin who likes to ipconfig and ifconfig on the fly.. ;-)
-- BillyReceived on Fri Mar 01 2002 - 07:05:03 CST